This invention relates to two-way mobile wireless communication, and more specifically to a method for delivering an electronic message via a mobile wireless message courier.
Current cellular phone users can use their cellular phones to reach the help center and make service requests, provided that they are in the footprint (coverage) of the base stations of their wireless service providers. If a cellular phone is integrated with location technology such as Global Position System (GPS), the location information of the user can be delivered to the help center automatically when the user calls the help center. But when users travel to the area where no wireless coverage exists (This may be due to the lack of wireless infrastructure or the terrain/building which blocks out the radio signals), they can no longer get help by making emergency service calls or 911 type calls. Therefore, there is a need for extending the communication capability provided by current wireless service providers in order to handle emergency situations.
This invention is a method for delivering electronic messages wirelessly when the sender of a message is outside the coverage area of its wireless service provider. The method relies on a third-party mobile wireless message courier which wirelessly receives the sender""s message when the courier enters the communication zone of the sender, stores the received message, and delivers the stored message when the courier enters the coverage area of its own wireless service provider.
The method exploits a broadcast wireless communication channel for peer-to-peer communication without the base station infrastructure of wireless service providers. Furthermore, the method requires a mobile unit which has two means of communications: one for communicating with its wireless service provider when it is in the coverage area and another for communicating with other parties through the peer-to-peer broadcast channel.
A requester who wants to reach the help center, and who is in the area not covered by its wireless service provider will repeatedly broadcast a help message which carries information such as the identity of the requester, the phone number of the party that the requester is trying to reach, the location of the requester, and the type of help the requester needs. If there is a mobile unit, such as a vehicle equipped with the aforementioned two means of communication, in the neighborhood of the requester, and the mobile unit is listening to the broadcast channel, the mobile unit can receive the broadcast message and store the message in its local storage. The mobile unit can connect to its wireless service provider when it enters the coverage area and deliver the stored help message on behalf of the requester. A mobile unit with the above characteristics is called a wireless message courier, or a courier for short, in the present invention.
A requester (the sender of a help message), in general, does not need to have both communication means that a wireless message courier has. A requester can have only one communication means, i.e., communicating over the broadcast channel, and always relies on wireless message couriers to deliver its messages. However, in the preferred embodiment of the present invention, all communication parties are assumed to have both communication means, which means that they all can potentially function as a wireless message courier. That is, a wireless message courier has two modes of operation. In a normal situation, it stays in the Relay mode and serves as a courier which listens to the broadcast channel for receiving possible broadcast messages. When a courier is in emergency situation, i.e., it needs other couriers to deliver a help message for itself, it stays in the Request mode and starts broadcasting help messages.